(Original post by Iorek)
Both the MCS and the JCW actually has 90% similar engine components, but the tuning differs between them. The turbo is also slightly bigger, but unlike the JCW the MCS has very little turbo lag.

Suspension wise, the JCW suspension can quite easily be fitted into a regular MCS.

But the thing that differs a lot is the clutch and gearbox, you drive the MCS hard and you're bound to blow a clutch or if you try to retune it to have a higher output you can just as well blow the gearbox as well. The JCW version somehow or rather does not give any problems with the clutch or gearbox even if you thrash the daylights out of it. My guess is they did toughen up the gearbox to cope with the extra horses.

If you're an enthusiastic driver, then it's best to get the JCW. Unless you will be under 21 when you get the keys to it, forget the MCS

Yeah this is the sort of thing I've been hearing. The packs are available to upgrade an MCS to JCW spec but the core components won't be the same quality, and so there's a more limited potential to upgrade later on. I also figure I'm unlikely to be buying brand new that often in my life so the one time I do it I want to get the thing I want. I just couldn't bear the thought of getting an MCS and then having a JCW pull up next to me at some lights lol. Cheers